Method of scouring wool



Patented Oct. 6, 1942 ton, Wia, assignors to The Institute of PaperGli'emistry', Appleton, Wis'.,- a corporation of--' Wisconsin NoDrawing.

Application September 18, 1939, 7 Serial N0. 295,454-

4 Claims. (Cl. 8-139) The present invention relates to an improvedprocess for scouring wool.

Prior to the present invention there were two chief scouring methods, 1.el, (1) the soap and alkali process, and (2) the solvent process. The

most prevalent of the two prior art methods was the soap and alkaliprocess utilizing as detergents water, soap andalkali for removal of thedirt, suint and grease. This process carried out'in an alkaline bath ata pH of 10.5-11.0 deleteriously affected the woolfiber and its use wasrecognized by the art to'present serious disadvantages. The

other process, utilizing relatively expensive organic solvents, was notvery effective andits use was generally recognized by the artas-unsatisfactory. and commercially impractical.

It is, therefore, the principal object of the present invention toprovide an improved processfor scouring wool.

Other objects will be apparent as the description hereinafter proceeds.

We havediscovered a commercially practical process for. effectivelyremoving dirt, suint, grease,

etc., from wool free from the above noted disadvantages.- Wool, forexample, treated in accordance with the present invention retains itsdesirable original fiber characteristics (1. e., its physical orchemical structures are not deleteriously impaired) and is much whiterand more open than wool treated by prior art processes. Physical tests,in fact, show the process of the present invention to increase desirablecharacteristics such as fiber elasticity, resiliency, felting qualities,etc., and decrease undesirable char-' acteristics such as fiberelongation.

The present invention provides the art with a satisfactory means forreadily obtaining improved wool flber heretofore unavailable.

The following example will .serve to illustrate the present invention:

Example About 1400 pounds of wool are first made ready at the feed endof the scouring train in accordance with general practice. About 10pounds of sodium glyceryl lauryl sulfate are next added to and dissolvedin the first scouring bowl contain- The temperature of the sulfatescouring solution for commercial purposes is ordinarily maintainedaround 150 F. which requires only about 1% minutes for scouring thewool. peratures with increased scouring time, e. g.,

- 320 F. for 3 minutes, may be employed. Scouring times may also varywith concentration as well as temperature-the optimum conditions beingreadily obtainable by. experimental tests. For usual operatingconditions scouring times of l-3 minutes and a temperature range of F.are ordinarily preferred.

. The pH of the securing solution should be 3.5 to 6.5, although a pH of4 to 6, which keeps the wool at its isoelectric point, is preferred.As'the wool grease generally has a pH value of about 8,

- it has been found necessary in most instances to add a small amount ofbufier to the scouring solu-.

tion inorder' to keep the pH within the proper Compounds such asglyceryl lauryl sulrated cotton seed oil acids are particularlyadaptable for use in the present invention. The alkali metal salts ofhigher aliphatic alcohol sulfates and higher fatty acid sulfates arerepresentative examples of other detergents suitable for use inaccordance with our process. In general, any jacidic organic ester orsoluble salt thereof being stable against hydrolysis in acid conditionand having detergent properties -may be employed. These materials areavailable on the open market or, if desired, may be prepared by knownchemical processes.

The wool treated in accordance with the presproven by many tests to befar superior to woo] treated in accordance with the prior art processes,such as the soap-alkali process. Wool; for

' abrasion. These properties are particularly important in the woolpaper-making felt art.

We have also discovered that wool treated by the acid procedure anddried to a moisture content of not less than 5 per cent, possesses amarked increase in tensile strength as compa'red to wool treatedsimilarly but dried to a moisture content below 5 per cent. Thisuniqueresult is Lower tem-.

ent invention in the acid scouring bath-has been just the reverse ofwool treated in'an alkaline scouring bath (e. g., the soap-alkaliprocess) in that such wool dried to a moisture content of not. less than5 per cent has a lower tensile strength than the same wool dried to lessthan 5 per cent water. These opposite drying effects also serve toemphasize the differences in the present scouring process and the otherprocesses available heretofore.

It will be understood that the present invention is not limited to theabove illustrative examples. All modifications coming within the spiritand scope 'of the present invention are intended to be covered by thefollowing claims.

'We claim:

1. The method of scouring wool for efiectively removing dirt, suint,grease and the-like, which comprises treating wool with an aqueousaliphatic sulfate detergent bath maintained at a temperature of about140 to 150 F. and a. pH of about 4 to 6, washing the treated-wool inwarm water and then drying the wool so that it contains at least about 5per cent moisture.

2. The method of scouring wool for effectively removing dirt, suint,grease and the like, which comprises treating wool with an aqueousalkali metal glyceryl lauryl sulfate detergent bath maintained at atemperature of about 140 to 150 F. and a pH of about 4 to 6, washing thetreated wool in warm water and then drying the wool so that it containsat least about ,5 per cent'moisture.

-3. The method of scouring wool for efiectively removing dirt, -suint,grease and the like, which comprises treating wool with an aqueoussulfate'd cotton seed oil acid detergent bath maintained at atemperature of about 140 to 150 F. and a pH BEN W. ROWLAND. DOUGLASmom/roman.

